dm crypt: prepare async callback fn

dm-crypt: Use crypto ablkcipher interface

Prepare callback function for async crypto operation.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 2ea3eb99c91f013b9b438754d5b6ab2c124a62b0..c45bd0e59dcce63cb7316db9853ed42c5ecd61fa 100644 (file)
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -406,11 +406,17 @@ static int crypt_convert_block(struct crypt_config *cc,
                                         ctx->sector);
 }
 
+static void kcryptd_async_done(struct crypto_async_request *async_req,
+                              int error);
 static void crypt_alloc_req(struct crypt_config *cc,
                            struct convert_context *ctx)
 {
        if (!cc->req)
                cc->req = mempool_alloc(cc->req_pool, GFP_NOIO);
+       ablkcipher_request_set_tfm(cc->req, cc->tfm);
+       ablkcipher_request_set_callback(cc->req, CRYPTO_TFM_REQ_MAY_BACKLOG |
+                                            CRYPTO_TFM_REQ_MAY_SLEEP,
+                                            kcryptd_async_done, ctx);
 }
 
 /*
@@ -615,6 +621,9 @@ static void kcryptd_io_read(struct dm_crypt_io *io)
 
 static void kcryptd_io_write(struct dm_crypt_io *io)
 {
+       struct bio *clone = io->ctx.bio_out;
+
+       generic_make_request(clone);
 }
 
 static void kcryptd_io(struct work_struct *work)
@@ -635,7 +644,8 @@ static void kcryptd_queue_io(struct dm_crypt_io *io)
        queue_work(cc->io_queue, &io->work);
 }
 
-static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int error)
+static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io,
+                                         int error, int async)
 {
        struct bio *clone = io->ctx.bio_out;
        struct crypt_config *cc = io->target->private;
@@ -653,8 +663,12 @@ static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int error)
        clone->bi_sector = cc->start + io->sector;
        io->sector += bio_sectors(clone);
 
-       atomic_inc(&io->pending);
-       generic_make_request(clone);
+       if (async)
+               kcryptd_queue_io(io);
+       else {
+               atomic_inc(&io->pending);
+               generic_make_request(clone);
+       }
 }
 
 static void kcryptd_crypt_write_convert_loop(struct dm_crypt_io *io)
@@ -682,7 +696,7 @@ static void kcryptd_crypt_write_convert_loop(struct dm_crypt_io *io)
 
                r = crypt_convert(cc, &io->ctx);
 
-               kcryptd_crypt_write_io_submit(io, r);
+               kcryptd_crypt_write_io_submit(io, r, 0);
                if (unlikely(r < 0))
                        return;
 
@@ -728,6 +742,29 @@ static void kcryptd_crypt_read_convert(struct dm_crypt_io *io)
        kcryptd_crypt_read_done(io, r);
 }
 
+static void kcryptd_async_done(struct crypto_async_request *async_req,
+                              int error)
+{
+       struct convert_context *ctx = async_req->data;
+       struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx);
+       struct crypt_config *cc = io->target->private;
+
+       if (error == -EINPROGRESS) {
+               complete(&ctx->restart);
+               return;
+       }
+
+       mempool_free(ablkcipher_request_cast(async_req), cc->req_pool);
+
+       if (!atomic_dec_and_test(&ctx->pending))
+               return;
+
+       if (bio_data_dir(io->base_bio) == READ)
+               kcryptd_crypt_read_done(io, error);
+       else
+               kcryptd_crypt_write_io_submit(io, error, 1);
+}
+
 static void kcryptd_crypt(struct work_struct *work)
 {
        struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);